JP2017535406A - Imageless implant revision surgery - Google Patents

Abstract

Systems and methods for planning and performing imageless implant revision surgery are discussed. For example, a method for generating a correction plan includes a step of collecting predefined parameters characterizing a target bone, generating a 3D model, collecting a plurality of surface points, and reshaping Generating a 3D model. The step of generating a 3D model of the target bone may be based on a first part of the predefined parameters. The step of generating the reshaped 3D model may be performed based on a plurality of surface points collected from a portion of the target bone surface.

Description

This application is a US provisional application entitled "Method for Planning and Performing CT-Less Implant Revision Surgery" filed on December 1, 2014, which is incorporated herein by reference in its entirety. Claims the benefit of the priority of 62 / 085,647.

  The present invention relates to the use of a robotic system in planning and performing orthopedic implant revision surgical procedures. One such type of robotic system, Precision Freehand Sculpting (referred to herein as “PFS”), is disclosed in more detail in US Pat. No. 6,757,582, which is incorporated herein by reference in its entirety. ing.

  Implant revision surgery is performed to remove orthopedic implants that have failed due to various causes such as loosening, movement, misalignment, wear, or other degradation. Once the existing implant is removed and the remaining bone surface is prepared, a new implant can be inserted. Implant revision surgery is typically performed using navigation methods to track the position of the tools involved, bones, and implants. However, modern navigation methods still require reevaluation of multiple cutting guides, measuring jigs, and osteotomy surfaces, resulting in an unnecessarily time consuming procedure.

  Problems with current revision techniques are exacerbated by the fact that removal of existing implants in revision procedures can result in additional damage to the bone surface, requiring additional bone resection to prepare for the insertion of a new implant. Become. In some existing systems, additional imaging may also be required to develop a new surgical plan. Care must be taken to ensure that the implant fits according to the patient's anatomy, while at the same time reducing the need for excessive instrumentation and imaging and reducing the time required to perform the procedure. There is currently no method for performing an implant revision surgical procedure that uses a method to ensure that the implant fits according to the patient's anatomy. Accordingly, it is an object of the present invention to provide an implant modified surgical procedure utilizing PFS that allows a surgeon to plan bone refinement and implant placement on a virtual model of the patient's anatomy. Is to provide a way to perform. The PFS system also allows the surgeon to accurately guide and perform bone resection, providing efficiency in terms of instrumentation used and time spent. Although the PFS system is discussed herein for example purposes, those skilled in the art will recognize only minor modifications that other robotic surgical systems such as Mako's Rio® system are readily apparent to those skilled in the art. It will be appreciated that it can be used with the method of the present invention.

  In addition to the various objects and advantages of the invention described above, various other objects and advantages of the invention will become apparent from the following more detailed description of the invention, particularly when read in conjunction with the accompanying drawings and It will be readily apparent to one of ordinary skill in the art when used in conjunction with the appended claims.

  Some embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings.

FIG. 2 illustrates an environment for operating a system for planning and performing imageless implant revision surgery according to an exemplary embodiment. 1 is a block diagram illustrating a system for planning and performing imageless implant revision surgery according to an exemplary embodiment. FIG. 6 is a flowchart illustrating a method for planning and performing imageless implant revision surgery according to an exemplary embodiment. 6 is a flowchart illustrating a method for creating a virtual 3D model for target bone resection in a modified implant procedure, according to an exemplary embodiment. 6 is a flowchart illustrating a method for creating a 3D model for target bone resection in a modified implant procedure, according to an exemplary embodiment. FIG. 4 illustrates a method for creating a 3D model used in a corrective procedure, according to an exemplary embodiment. FIG. 6 is a schematic diagram of a machine in an exemplary form of a computer system in which a set of instructions can be executed to cause the machine to execute any one or more of the methodologies discussed herein.

Overview The inventors are able to adequately describe the specific shape and condition of the target bone, among other things, current techniques used in orthopedic implant revision surgery, such as revision of total knee replacement. It recognizes that it does not provide the surgeon with a way to visualize and expand the implant, and does not provide patient-specific results to customize the location of the ablation and implant.

  Furthermore, current systems for performing revision knee surgery require extensive instrumentation. This is required to achieve both alignment and placement of the selected implant. These instruments include an alignment jig, a rod, and a plurality of cutting blocks. The instruments rely primarily on the generalized assumptions of the anatomy, and the systems and methods discussed herein are suitable for the patient's appropriate cutting plan derived during individual surgery. Allows complete replacement.

  Currently used instruments require fixation to the bone being operated near the implant interface. Due to the nature of the pathology that requires surgery, the quality of the bone is often not good, causing inadequate or uneasy fixation of the cutting block and alignment jig, which often causes undesirable movement of the jig, Inaccurate implant placement with adverse effects on subsequent patient outcomes. The nature of the present invention allows this possibility to be overcome by placing the tracker in a reliable fixation with better quality bone away from the surgical area.

  By eliminating the need for these instruments and their associated costs and burdens (such as sterilization, handling, transportation, damage in transit), the present invention itself provides financial and logistical benefits to the user. It will be.

  The following non-limiting examples detail certain aspects of the present systems and methods that solve and provide benefits for the problems discussed herein.

  Example 1 can include a method for creating a revision plan for use during an imageless implant revision procedure. The method can include generating a 3D model, receiving a plurality of surface points, and generating a reshaped 3D model. A 3D model is generated to model the shape of at least a portion of the target bone associated with the implant modification procedure. A plurality of surface points are collected over the portion of the target bone surface associated with the implant modification procedure. A reshaped 3D model is generated based on the 3D model and a plurality of surface points collected from the surface portion of the target bone.

  In Example 2, the method of Example 1 can optionally include the step of generating a correction plan for preparing the target bone for implantation of the prosthetic implant.

  In Example 3, the method of Example 2 may optionally include the step of controlling a surgical cutting instrument that is tracked during target bone resection according to a modified plan.

  In Example 4, any of the methods of Examples 1-3 can optionally include generating a voxelized 3D cylinder that surrounds a portion of the target bone associated with the implant modification procedure. In some examples, the cylinder is larger in all dimensions compared to the target bone portion associated with the implant modification procedure.

  In Example 5, any method of Examples 1 through 4 uses a voxelized 3D model to generate a 3D model and a voxel in a voxelized 3D model based on multiple surface points. Updating may optionally include generating a reshaped 3D model.

  In Example 6, the method of Example 5 can optionally include updating voxels in the voxelized 3D model, including performing volume subtraction from the 3D model based on the plurality of surface points. .

  In Example 7, any of the methods of Examples 1-6 can optionally include receiving a predefined set of parameters from the tracked surgical instrument that characterizes the target bone, and a 3D model Generating a target bone dimension from a predefined set of parameters.

  In Example 8, any of the methods of Examples 1-7 may optionally include the step of iteratively generating a reshaped 3D model during the collection of multiple surface points.

  Example 9 can include a system for planning and performing imageless implant revision surgery, including creating a revision plan. The system can include a surgical instrument, a tracking system, and a control system. The surgical instrument can include a tracking array. The tracking system can include a tracking sensor and can monitor the three-dimensional position and orientation of the surgical instrument and the three-dimensional position and orientation of at least one target bone of the implant host in real time. The control system can include a communication interface and one or more processors coupled to the memory device. The communication interface may be coupled to the tracking system to receive tracking information identifying the current surgical instrument position and the current target bone position. The memory device, when executed by one or more processors, collects predefined parameters, generates a 3D model, collects multiple surface points, and reshapes 3D Instructions can be included that cause the control system to perform operations including generating a model. The predefined parameters characterize the target bone in the implant correction procedure. The 3D model is generated from some of the predefined parameters to model the shape of at least a portion of the target bone. Optionally, the second part of the predefined parameters is used to align the 3D model on the target bone in the working coordinate system. A plurality of surface points are collected over the portion of the target bone surface associated with the implant modification procedure. A reshaped 3D model is generated based on the 3D model and a plurality of surface points collected from the surface portion of the target bone.

  In Example 10, the system of Example 9 can optionally include a surgical instrument having at least one of a cutting bar, bar guard, flat plate probe attachment, and point probe.

  In Example 11, the system of Example 10 optionally includes collecting predefined parameters or multiple surface points using one of a cutting bar, bar guard, flat probe attachment, and point probe. be able to.

  In Example 12, the optional system of Examples 9-11 may optionally include a control system that further performs operations including generating a correction plan for preparing a target bone for implanting a prosthetic implant. it can.

  In Example 13, the system of Example 12 can optionally include a communication interface coupled to the surgical instrument to send a control signal to control the cutting bar. The control system also generates a control signal for controlling the surgical instrument during target bone resection according to the correction plan, and communicates the generated control signal to the surgical instrument via the communication interface. Including operations can be performed.

  In Example 14, the optional system of Examples 9 to 13 optionally includes generating a 3D model by generating a voxelized 3D cylinder that surrounds the portion of the target bone associated with the implant modification procedure. Can do.

  In Example 15, the system of Example 14 can optionally include generating a reshaped 3D model by performing volume subtraction from the 3D model based on the plurality of surface points.

  In Example 16, any system of Examples 9-15 can optionally include generating a 3D model by accessing a pre-operative medical image of the target bone to generate a 3D model.

  In Example 17, any system of Examples 9-16 can optionally include iteratively generating a reshaped model during the collection of multiple surface points.

  Example 18 includes a machine-readable storage medium having instructions for performing the method described in any one of Examples 1-9 when executed in a system for navigation and control of a surgical instrument. it can.

  Example 19 can include a computer-implemented method for planning an implant revision procedure. The method may include generating a 3D voxelization model, receiving a plurality of data points, calculating a set of discarded voxels, and generating a reshaped 3D voxelization model. it can. A 3D voxelized model may be generated to model the target bone portion associated with the implant modification procedure, and the model is at least as large as the target bone portion in all dimensions. is there. A plurality of data points are received from a tracking system that tracks an instrument of known geometry as the instrument is traced along the target bone surface. A set of discarded voxels to be removed from the model is calculated based at least in part on the plurality of data points. A reshaped 3D voxelization model is generated based on the set of discarded voxels.

Definitions Implant—For purposes of this specification and the related claims, the term “implant” is used to refer to a prosthetic device or structure manufactured to replace or augment a biological structure. Is done. For example, in a total hip replacement procedure, a prosthetic acetabular cup (implant) is used to replace or augment a patient's worn or damaged acetabulum. The term “implant” is generally considered to mean an artificial structure (as opposed to an implant), but for purposes herein, an implant replaces or enhances a biological structure. Biological tissue or material to be transplanted.

  Implant Host—For purposes of this specification and the associated claims, the term “implant host” is used to refer to a patient. In certain instances, the term implant host may also be used more specifically to refer to a particular joint or position of an intended implant within a particular patient anatomy. For example, in a total hip replacement procedure, the implant host may refer to the patient's hip joint to be replaced or repaired.

  Real-time-For purposes of this specification and the associated claims, the term “real-time” refers to a calculation that is performed immediately when an event occurs or input is received by an operable system. Or used to refer to an action. However, the use of the term “real time” is not intended to preclude operations that result in some latency between input and response, as long as latency is an unintended result induced by the performance characteristics of the machine.

DETAILED DESCRIPTION Exemplary systems and methods for planning and performing imageless (CT-less) implant revision surgery are described. In some exemplary embodiments, the systems and methods discussed herein can include a combination of a tracked point probe and a computer controlled surgical cutting instrument. In one example, an optically tracked point probe and a computer controlled surgical cutting instrument are used to replace a defective orthopedic implant such as a defective total knee replacement (TKA). It can be used to plan and execute corrective actions. In one example, the surgeon uses a point probe to map the actual surface of the target bone that requires a new implant in three dimensions. Mapping is performed after removing defective or worn implants, as well as removing any pathological or otherwise undesirable bone. The computer system can initiate the mapping process with a voxelized 3D model of the patient's bone aligned with landmark positions obtained using a tracked point probe or similar tracked surgical instrument. During the mapping process, tracked point probes, cutting bars, bar guards, or flat probe attachments are used on the cutting instrument to reshape the voxelized 3D model based on actual surface data obtained from the patient's bone Is done. Once the final 3D model is complete, the surgeon can move through the virtual 3D model layer by layer to evaluate the position and fit of the modified implant. The detailed evaluation enabled by the virtual 3D model generated using actual 3D surface data allows for accurate fit evaluation (size and position), selection of augments, and placement of augments. Once the modified implant and any augments are virtually placed in the 3D model environment, the system will be implemented using a tracked and computer controlled cutting instrument such as the PFS discussed above. A surgical cutting plan can be generated.

  The methods of performing the corrective procedures discussed herein allow the surgeon to more accurately place the corrective implants and augments while avoiding the need for cutting guides and other complex instrumentation. The actual effects of the discussed system in the operating room include fewer trays, less sterilization, and lower cost.

  The following specification and the associated figures illustrate exemplary embodiments of the invention having specific details. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details. It will also be apparent that the computer controlled implant positioning system is not limited to the examples provided and may include other scenarios not specifically discussed.

  FIG. 1 is a diagram of a system 100 for performing an imageless (CT-less) revision surgical procedure using a robotic system. System 100 includes a surgical cutting tool 150 having an associated optical tracking frame 155 (also referred to as tracking array 155), a graphical user interface 130, an optical tracking system 140, and a patient tracking frame 120 (also referred to as tracking array 120). including. This figure also includes an incision 110 through which knee correction surgery can be performed. In one example, the illustrated robotic surgical system 100 represents a handheld computer controlled surgical robotic system, such as the Navio® Surgical System of Blue Belt Technologies of Plymouth, Minnesota. The illustrated robotic system uses an optical tracking system coupled to the robot controller to track and control the handheld surgical instrument. For example, the optical tracking system 140 may include a tracking array 155 coupled to the surgical tool 150 to track the position of the instrument relative to the target bone (e.g., femur and tibia for knee treatment), Track with the combined tracking array 120.

  FIG. 2 is a block diagram illustrating a system 200 for performing an imageless (CT-less) revision surgical procedure, according to an example embodiment. In one example, the system 200 can include a control system 210, a tracking system 140, and a surgical instrument 150. Optionally, system 200 can also include display device 130 and database 230. In one example, these components may include navigation and control of a surgical instrument 150 that may include, among other things, navigation and control of a cutting tool or point probe used during orthopedic (or similar) prosthetic implant revision surgery. Can be combined to provide control.

  The control system 210 can include one or more computing devices configured to coordinate information received from the tracking system 130 and provide control to the surgical instrument 150. In one example, the control system 210 can include a planning module 212, a navigation module 214, a control module 216, and a communication interface 218. In a particular example, the planning module 212 can provide a pre-operative planning service that gives the clinician the ability to virtually plan the procedure before reshaping the target joint during a corrective procedure on the patient. Part of the planning process performed within the planning module is part of U.S. Patent No. 6,205,411 entitled "Computer-assisted Surgery Planner and Intra-Operative Guidance System" to Digioia et al. Discussing additional approaches to preoperative planning. Operations similar to those discussed in. US Pat. No. 6,205,411 is hereby incorporated by reference in its entirety.

  In one example, such as total knee replacement (TKA) modifications, the planning module 212 may be used to manipulate the virtual model of the implant with respect to the virtual implant host model. As discussed in more detail below, a virtual model of the implant host (the joint to be modified) can be created through the use of a point probe or similar instrument that is tracked by the optical tracking system 140. The control system 210, in some examples the planning module 212, collects data from the target joint surface to recreate a virtual model of the patient's actual anatomy. Specifically, in revision surgery, this method can increase the accuracy of the planning process by using data collected without intraoperative images after the existing implants have been removed. Collecting surface data from the target bone also allows for repetitive reshaping of the target bone to ensure proper fit of the new prosthetic implant and optimization of anatomical alignment Can do.

  In one example, the navigation module 214 can adjust the tracking of the position and orientation of the implant, implant host, and surgical instrument 150. In certain examples, the navigation module 214 may also coordinate the tracking of virtual models used during pre-operative and intra-operative planning within the planning module 212. Tracking the virtual model can include operations such as alignment of the virtual model with the implant host with data obtained via the tracking system 140. In these examples, the navigation module 214 receives input from the tracking system 140 regarding the physical position and orientation of the surgical instrument 150 and implant host. Implant host tracking may include tracking a plurality of individual bone structures using a tracking array 120 or the like. For example, during a total knee replacement procedure, tracking system 140 may track the femur and tibia individually using a tracking device secured to the individual bone (as shown in FIG. 1).

  In one example, the control module 216 can process the information provided by the navigation module 214 to generate control signals that control the surgical instrument 150. In certain examples, the control module 216 can also cooperate with the navigation module 214 to generate visual animations to assist the surgeon during the surgical procedure. The visual animation may be displayed via a display device such as display device 130. In one example, the visual animation may include real-time 3D representations of the implant, implant host, and surgical instrument 150, among others. In certain examples, the visual animation is color coded to further assist the surgeon with respect to implant positioning and orientation.

  In one example, communication interface 218 facilitates communication between control system 210 and external systems and devices. The communication interface 218 can include both wired and wireless communication interfaces, such as Ethernet®, IEEE 802.11 wireless, or Bluetooth®, among others. As shown in FIG. 1, in this example, the main external system connected via communication interface 218 includes a tracking system 140 and a surgical instrument 150. Although not shown, database 230 and display device 130 may also be connected to control system 210 via communication interface 218, among other devices. In one example, the communication interface 218 communicates with other modules and hardware systems in the control system 210 via an internal bus.

  In one example, the tracking system 140 provides position and orientation information regarding the anatomical portion of the surgical device and implant host to assist in navigation and control of the semi-active robotic surgical device. The tracking system 140 can include a tracker (eg, tracking array 120) that includes or otherwise provides tracking data based on at least three positions and at least three angles. The tracker includes one or more first tracking markers associated with the implant host and one or more second markers associated with the surgical device (e.g., surgical instrument 150) Can do. The marker or some of the markers may be one or more of an infrared source, a radio frequency (RF) source, an ultrasound source, and / or a transmitter. The tracking system 140 can thus be an infrared tracking system, an optical tracking system, an ultrasound tracking system, an inertial tracking system, a wired tracking system, and / or an RF tracking system. One exemplary tracking system may be the OPTOTRAK® 3D motion and position measurement and tracking system described herein, but those skilled in the art will recognize other tracking systems with other accuracy and / or resolution. It will be appreciated that it can be used.

  US Pat. No. 6,757,582 entitled “Methods and Systems to Control a Shaping Tool” to Brisson et al. Provides further details regarding the use of tracking systems such as tracking system 140 in a surgical environment. US Pat. No. 6,757,582 (the '582 patent) is hereby incorporated by reference in its entirety.

  In one example, the surgeon can use the surgical instrument 150 to shape the target bone to accommodate a new prosthetic implant in place of the failed existing implant. For example, as discussed above, modifying the TKA by removing the prosthetic implant that forms the prosthetic knee, reshaping the femur and tibia, and implanting the new prosthetic implant to form a new prosthetic knee It is not uncommon to need To assist in performing the correction, system 200 tracks and cuts the surgical cutting instrument to perform an accurate cut according to a virtual plan generated after removal of the old prosthesis (as discussed in more detail below). Can be controlled.

  Referring to FIG. 3, a method 300 is provided for performing a corrective surgical procedure using a robotic system such as system 100 or 200. In this example, method 300 includes tool selection and calibration at 305, removal of an existing implant at 310, attaching a tracking array at 315, collecting target joint data at 320, removing an existing implant at 325. Collecting surface points at 330, planning implant size and location at 335, balancing gap spacing at 340, planning augmentation at 345, displaying bone improvement plans at 350 , Excising bone at 355, inserting a new implant at 360, and collecting and displaying motion range data at 365. Method 300 may be performed with more or fewer operations in certain examples. For example, in some exemplary corrective procedures, balancing the joints or gaps at 340 may be an optional procedure.

  According to step 305, the robotic system is connected and calibrated to the selected surgical tool and bar type. The tool is calibrated and verified for tracking during the surgical procedure. An overall surgical setup 100 is shown in FIG. 1, and additional details provided in FIG. 2 discuss system 200, which in some examples is an extension of system 100.

  As shown in step 310, an initial incision 110 is made to allow the surgeon to access and remove the existing implant. In embodiments, the surgeon often needs to use a hammer to facilitate removal of the implant from the bone, if the tracker is installed prior to the initial relaxation and removal process. The implant is removed prior to installing any tracker, such as the tracking array 120, as it may relax the tracker. After the existing implant is relaxed and removed, the surgeon removes any degraded or pathological bone that was behind the implant. In a particular example, the implant is then reinserted as much as possible to allow data collection for planning purposes. An alternative embodiment provides a tracker pin with a removable connection so that the tracker is removed from the pin when the pin is first inserted into place and then the implant is removed. Either way, these use infrared or other optical “line-of-sight” cameras such as tracking system 140 that also monitors the real-time position of any tracked tool such as surgical instrument 150 used by the surgeon. The tracking array 120 is then attached (or possibly reattached) to the femur and tibia to enable real-time position monitoring of the bone (315).

  According to step 320, a number of checkpoints and reference position data points are collected (also referred to as landmarks and predefined parameters). The position of the point probe used to collect coordinate points on the bone and implant surfaces is verified with respect to the position of the tip relative to the tracker. Checkpoints are established on the femur and tibia bones including the heel as pre-established stationary reference points touched at the point probe tip in the system. At various points during the overall procedure, these points will be touched again by the point probe to ensure accuracy within the tracking system as a whole. Typically, the hip center is calculated by rotating the tracked femur on a circle centered on the hip until sufficient data is collected.

  Next, the center of the knee is determined. Still referring to step 320, femoral landmark points are collected by palpation of what is present at the tip of the point probe. Such femoral landmark points are, for example, the center of the knee, the foremost point, the most distal point, the last point, and the medial and lateral epicondyles as long as these points exist and are reliable. Including points. In alternative embodiments, statistics may be used instead of these actual points. Next, a rotation reference for the femur is determined. The joint line reference is then determined by the femur and tibia landmarks. In some patients, joint line criteria are difficult to determine, and in some embodiments, other knee joints can be used for landmarks.

  Still within the context of step 320, tibial landmark points, including the tibial knee center and the medial and lateral points of most of the tibia, may be collected by palpation with the tip of the point probe. In addition, a tibial rotation reference is determined. Next, motion range data including maximum varus and valgus in joint extension and flexion is collected for the purpose of balancing the gap.

  In step 325, the existing implant is removed again (assuming that the particular procedure being performed allows reinsertion in step 310), and in step 330, then, for example, with a point probe tip or a drill tip. A number of points are collected on the remaining bone surfaces of the femur and tibia by brushing or scraping the entire remaining bone. This so-called “free collection” is actually a trace or “painting” of the remaining large part of the bone, and a 3D model or surface map of the bone surface in a computerized planning system such as the control system 210. Used to create. The created 3D model of the remaining bone is then used as a basis for planning the procedure and the required implant size. Typically, landmark points are used to create a starting volume (initial 3D model), which is then trimmed to represent the actual size of the remaining bone during this free collection step. . In an alternative embodiment, an infrared pointer may be incorporated into the handpiece, the location of the infrared light on the bone may be recorded by the system, and a 3D model of an existing bone may be created as well.

  In a particular example, the system uses the landmark and other information collected in step 320 to create a joint volume (voxelized) model. The virtual 3D model is aligned with the actual bone structure via tracking data such as tracking array 120 and point probe tracking (surgical instrument 150) via tracking array 155. Thereafter, during the collection of surface data in step 330, the volume virtual 3D model is reshaped to match the actual surface of the target bone. This process of iteratively reshaping 3D models generated from landmarks and other patient-specific information results in a very accurate 3D model of the actual target bone that can be used throughout the planning process. Substantial reshaping of the 3D model provides the final result faster and more accurately than intraoperative imaging and without the logistical difficulties associated with intraoperative CT or similar scanning techniques.

  According to step 335, the size and location of the femoral and tibial implants are then established on the model in system 200. Optionally, the balancing of the gap between the femur and tibia is then planned at step 340. As used herein, balancing the gap ensures that the ligaments and soft tissue are properly tensioned to support post-procedural knee stability and proper range of motion. Refers to that. In an embodiment, balancing is achieved by rotating the femoral component when the knee is flexed. During extension, the knee is balanced by opening or thinning the ligament, but if the ligament is released, it needs to be remeasured.

  Once the ideal implant size and location has been selected, the system 200 can optionally provide a cross-sectional view for evaluation, and the potential use of a femoral or tibia prosthetic augment is determined in step 345. Can be evaluated and planned. If there is a gap between the existing bone and the back side of the implant, such as when the pathological bone behind the previous implant needs to be removed, augments are used to eliminate the gap. As a result, the cutting plan is changed to accommodate the augment.

  The femur and tibia checkpoints are then verified to ensure that the cut is made as intended. Finally, according to 350, the bone improvement plan obtained in the previous planning step is displayed on the remaining bone representation created as a result of the free collection step. This information is then displayed to the surgeon on the monitor 130 in the operating room. Next, at step 355, bone resection is performed, and at step 360, once the bone is fully prepared according to the bone improvement plan, the implant is inserted.

  FIG. 4 is a flowchart illustrating a method 400 for creating a virtual 3D model for target bone resection in a modified implant procedure, according to an exemplary embodiment. In this example, method 400 calibrates the point probe at 410, collects landmarks at 420, creates a 3D model at 430, optionally aligns the 3D model at 440, collects surface data at 450 Operations such as generating, reshaping the 3D model at 460, and optionally generating a modified plan at 470. Although the method 400 is illustrated in FIG. 4 as including the various operations discussed above, in other examples, the operations may be in a different order, or similar methods may be less or more Many actions may be included.

  At 410, the method 400 can optionally begin with calibration of the surgical instrument 150. Calibration involves aligning the working end of the surgical instrument 150 within the three-dimensional coordinate system tracked by the tracking system so that the tracking system 140 can accurately position the surgical instrument 150. Calibration can be performed by touching the working end of a surgical instrument, such as a point probe or cutting bar, with an object having a known coordinate in the coordinate space of the tracking system.

  At 420, the method 400 continues with the control system 210 collecting landmarks and other predefined parameters of the target bone. In this example, surgical instrument 150 may be used to touch the landmark while tracking system 140 sends position data to control system 210. At 430, the method 400 continues the control system 210, such as within the planning module 212, to create an initial 3D model of the target implant region of the target bone. In one example, the 3D model is a voxelized model of at least a portion of the target bone intended to accept a new implant. A 3D model can be generated from a statistical bone model using landmarks and other predefined parameters to select size and shape from a database of statistical models. In other examples, the 3D model can be generated from a pre-operative medical imaging scan such as a CT scan. In some examples, landmarks and other predefined parameters are used to generate a basic 3D model as a starting point without any other input.

  At 440, the method 400 continues with the control system 210 aligning the initial 3D model to the target bone. The method 400 continues at 450 with the control system 210 collecting surface data from the target bone. Surface data is received by the control system 210 from the tracking system 140 while the tracking system 140 monitors the position of the surgical instrument 150. Surface data may be collected using various attachments on the surgical instrument 150, such as, among others, point probe attachments, cutting bars, bar guards, or flat probe attachments. Surface data collection is performed after the defective or worn prosthesis is removed and after any additional undesirable bone is removed. In certain examples, the collection of surface points may be guided through the display of an interactive animation (illustration) of the target bone surface, which indicates where it still needs to be collected on the target bone surface It can be a technique. Color coding or similar techniques can be used to indicate past and required point collection positions.

  At 460, the method 400 continues by generating a reshaped 3D model based on the target bone surface data received by the control system 210. The reshaped 3D model becomes an accurate virtual representation of the actual surface contour of the target bone, which allows for an accurate planning of the size and position of the modified implant. The generation of the reshaped 3D model can be an iterative process where the control system 210 updates the 3D model as surface data is received from the tracking system 140. Display of the reshaped 3D model, such as iterative generation and display device 130, allows the surgeon to determine how well the target bone surface was captured during the planning portion of the corrective procedure Enable.

  At 470, the method 400 may end with the control system 210 generating a modified plan based on the reshaped 3D model. The generation of the correction plan can include receiving implant selection and positioning input from the surgeon. In some examples, the system can suggest an initial implant size and position based on the analysis of the reshaped 3D model. Once the size and position of the implant is determined, the reshaped 3D model can be further analyzed to determine if augments need to be included to optimize the fit of the modified implant. The voxelized 3D model allows for efficient display and virtual manipulation that allows the surgeon to move quickly between layers of the 3D model to assess fit. Finally, the control system 210 can generate a cutting or resection plan to reshape the target bone to best fit the regenerative implant and any selected augment.

  In one embodiment, the method is utilized to perform a correction procedure on a total knee replacement patient having a plurality of pre-existing prostheses that include both femoral and tibial components.

  While presently preferred and various alternative embodiments of the present invention have been described in detail above in accordance with patent law, various other modifications and alternative embodiments are within the spirit of the invention or the appended claims. It should be understood that those skilled in the art will recognize without departing from any of these.

  FIG. 5 is a flowchart illustrating a method 500 for creating a 3D model for target bone resection in a modified implant procedure, according to an exemplary embodiment. Method 500 illustrates some alternatives of the operations discussed with reference to method 400. In this example, the method 500 optionally collects landmark or target bone parameters at 510, generates a 3D model of the target bone at 520, and receives surface data from the target bone at 530. And operations such as generating a reshaped 3D model at 540. In this example, the 3D model is a voxelized volume-based approximation of the target bone. Because of the reshaping technique, the voxelized 3D model need only have a volume that is large enough to surround the portion of the target bone that will be involved in the correction procedure. For example, the method 500 can begin with a cylinder or similar 3D polygon surrounding the distal end of the femur. FIG. 6 provides additional diagrams in the 2D scheme of the reshaping process discussed below.

  At 510, the method 500 can optionally begin with the control system 210 receiving data describing at least the basic dimensions of the target bone. In some examples, the control system 210 will receive landmarks and other size or shape parameters from a tracked surgical instrument in contact with the target bone surface. At 520, the method 500 continues with the control system 210 generating an initial 3D model of the target bone. As discussed above, the initial 3D model can be as simple as a voxelized cylinder of sufficient size to encompass all relevant bone surfaces. For example, if the distal femur is the target bone region for the corrective procedure, the voxelized cylinder will have both the condyle and the length of the femur proximate the distal end longer than any envisioned implant Can be made large enough to surround. As shown in FIG. 6 in two dimensions, the starting model 620 need only surround the relevant bone surface (compare the starting model 620 with the reshaped model 640).

  At 530, method 500 can continue by performing volume subtraction on the initial 3D model based on target bone surface data received by control system 210 from a tracked surgical instrument, such as surgical instrument 150. . As surgical instrument 150 moves over the target bone surface, position data from tracking system 140 is used to reclassify the voxels in the initial 3D model as boundary voxels or waste voxels, which are removed. Is done. In some examples, boundary voxels can be smoothed or otherwise manipulated to produce a final reshaped 3D model. At 540, method 500 ends with control system 210 generating a final reshaped 3D model. In some examples, a final reshaped 3D model is generated when the surgeon indicates that all surface points on the target bone have been captured. In other examples, the control system 210 determines from the received surface data input when the reshaped 3D model contains sufficient details to generate a usable model. For example, the system may determine that when it has a sufficient number of data points to form a continuous surface, or when the interpolation between points falls below a predefined threshold.

  FIG. 6 is a diagram illustrating a method for creating a 3D model to be used in a correction procedure, according to an exemplary embodiment. FIG. 6 is divided into a physical world diagram 600 on the left side and a computer model diagram 610 on the right side. The physical world diagram 600 shows an example of a target bone surface mapping with a surgical instrument 150 that includes a tracking array 155. Computer model diagram 610 illustrates a volume subtraction method for transitioning from a start model 620 to a reshape model 640. In some examples, the control system 210 generates a graphical user interface animation similar to the computer model diagram 610. A starting model 620 is shown with a surgical instrument model 625. As the physical counterpart (surgical instrument 150) collects surface data from the target bone, surgical instrument model 625 “airs” or discards the voxel (shown in two dimensions for clarity). Voxel 630 is shown as being changed. Reshaping model 640 is shown with waste voxels 635 (also referred to as “air”) and bone voxels 650.

Modules, Components, and Logic Certain embodiments of computer systems, such as the control system 210 and tracking system 140 described herein, may include logic, or several components, modules, or mechanisms. A module may constitute either a software module (eg, code embodied on a machine-readable medium or in a transmission signal), or a hardware module. A hardware module is a tangible unit capable of performing a specific operation and may be configured or arranged in a specific manner. In an exemplary embodiment, one or more computer systems (e.g., a stand-alone client or server computer system), or one or more hardware modules (e.g., a processor or group of processors) of a computer system, It may be configured by software (eg, an application or application portion) as a hardware module that operates to perform the specific operations described in the specification.

  In various embodiments, the hardware module may be implemented mechanically or electronically. For example, a hardware module is a dedicated circuit or logic that is permanently configured to perform a specific operation (e.g., as a dedicated processor such as a field programmable gate array (FPGA) or application specific integrated circuit (ASIC)). May be provided. A hardware module may also comprise programmable logic or circuitry (eg, included within a general purpose processor or other programmable processor) that is temporarily configured by software to perform a particular operation. The decision to implement a hardware module mechanically in a dedicated permanently configured circuit or in a temporarily configured circuit (e.g. configured by software) can be determined by cost and time considerations It will be understood.

  Thus, the term `` hardware module '' has been permanently configured to operate in a specific manner and / or physically configured to perform the specific operations described herein ( It should be understood to encompass tangible entities that are, for example, wired) or temporarily configured (eg, programmed) entities. Considering embodiments in which hardware modules are temporarily configured (eg, programmed), each hardware module need not be configured or instantiated at any given time. For example, when the hardware module includes a general-purpose processor configured using software, the general-purpose processor may be configured as different hardware modules at different times. Thus, the software may, for example, configure a processor to configure a particular hardware module at a certain time and a different hardware module at a different time.

  A hardware module can provide information to and receive information from other hardware modules. Accordingly, the described hardware modules may be considered to be communicatively coupled. If multiple such hardware modules are present simultaneously, communication may be achieved by signal transmission connecting the hardware modules (eg, via appropriate circuitry and buses). In embodiments where multiple hardware modules are configured or instantiated at different times, communication between such hardware modules is achieved, for example, by storing and retrieving information in a memory structure to which the multiple hardware modules have access. May be achieved. For example, one hardware module may perform an operation and store the output of the operation in a memory device to which the hardware module is communicatively coupled. The additional hardware module may then access the memory device later to retrieve and process the stored output. A hardware module may also initiate communication with an input device or output device and may operate on a resource (eg, a collection of information).

  The various operations of the exemplary methods described herein may be one or more temporarily configured (eg, by software) or configured permanently to perform related operations. It may be executed at least in part by the processor. Whether configured temporarily or permanently, such a processor may constitute a processor-implemented module that operates to perform one or more operations or functions. The modules referred to herein may comprise processor-implemented modules in some exemplary embodiments.

  Similarly, the methods described herein may be implemented at least in part by a processor. For example, at least some of the method operations may be performed by one or more processors, or processor-implemented modules. The execution of specific operations may not only exist within a single machine, but may be distributed to one or more processors located on several machines. In some exemplary embodiments, one or more processors may be located in a single location (e.g., in a home environment, an office environment, or as a server farm), although other embodiments The processors may then be distributed in several places.

Electronic Devices and Systems Exemplary embodiments may be implemented in digital electronic circuitry or in computer hardware, firmware, software, or combinations thereof. Exemplary embodiments use a computer program product to execute, for example, or to control the operation of a data processing device, eg, a programmable processor, a computer, or multiple computers. May be implemented using a computer program tangibly embodied in an information carrier, eg, in a machine-readable medium. Certain exemplary embodiments of surgical instrument 150 may include a machine-readable medium that stores executable instructions to be executed by surgical instrument 150.

  A computer program may be written in any form of programming language, including a compiled or interpreted language, and as a stand-alone program or other unit suitable for use in a module, subroutine, or computing environment Can be deployed in any form, including as A computer program may be deployed to be executed on one computer at one site or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network.

  In an exemplary embodiment, operations may be performed by one or more programmable processors that execute a computer program to perform functions by operating on input data and generating output. . The method operations may also be performed by dedicated logic circuitry (eg, FPGA or ASIC), and the devices of the exemplary embodiments may be implemented as dedicated logic circuitry (eg, FPGA or ASIC).

  The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The client and server relationship is caused by computer programs running on the respective computers and having a client-server relationship with each other. It will be appreciated that in embodiments deploying programmable computing systems, both hardware and software architectures need to be considered. Specifically, specific functions can be implemented with permanently configured hardware (for example, ASIC) or temporarily configured with hardware (for example, a combination of software and a programmable processor). It will be appreciated that the choice of whether to implement or a combination of permanently configured hardware and temporarily configured hardware may be a design choice. The following shows hardware (eg, machine) and software architectures that may be deployed in various exemplary embodiments.

Exemplary Machine Architecture and Machine-Readable Medium FIG. 7 is a block diagram of a machine in an exemplary form of a computer system 700, within the computer system 700, any one of the methodologies discussed herein or Instructions that cause a machine to execute more than one may be executed. In alternative embodiments, the machine may operate as a stand-alone device or be connected (eg, networked) with other machines. In a networked deployment, the machine may operate as a server machine or client machine in a server-client network environment or as a peer machine in a peer-to-peer (or distributed) network environment. The machine may be a personal computer (PC), a tablet PC, or any machine capable of executing instructions (sequentially or otherwise) that specify actions to be taken by the machine. Further, although only a single machine is shown, the term “machine” also refers to a set of instructions (or a plurality of instructions) for performing any one or more of the methodologies discussed herein. Including any set of machines that perform the set) individually or jointly.

  Exemplary computer system 700 includes a processor 702 (e.g., a central processing unit (CPU), a graphics processing unit (GPU), or both), a main memory 704, and a static memory 706, which are connected to a bus 708. Communicate with each other via Computer system 700 may further include a video display unit 710 (eg, a liquid crystal display (LCD) or a cathode ray tube (CRT)). The computer system 700 also includes an alphanumeric input device 712 (e.g., a keyboard), a user interface (UI) navigation device (or cursor control device) 714 (e.g., a mouse), a disk drive unit 716, and a signal generation device 718 (e.g., , Speaker) and network interface device 720.

Machine-readable media A disk drive unit (storage device) 716 is one or more sets of instructions and data structures (e.g., implemented or used by any one or more of the methodologies or functions described herein (e.g., Software) 724 is stored on the machine-readable medium 722. The instructions 724 may also be wholly or at least partially resident in the main memory 704, static memory 706, and / or processor 702 during its execution by the computer system 700, main memory 704, and processor 702. It also constitutes a machine-readable medium or storage device.

  Although the machine-readable medium 722 is shown in the exemplary embodiment to be a single medium, the term “machine-readable medium” refers to a single item that stores one or more instructions or data structures. Media or multiple media (eg, centralized or distributed databases, and / or associated caches and servers). The term “machine-readable medium” can also store, encode, or carry instructions for execution by a machine, causing a machine to execute any one or more of the methodologies of the present invention, Or any tangible medium capable of storing, encoding, or carrying data structures used by or associated with such instructions. The term “machine-readable medium” is therefore to be interpreted as including, but not limited to, solid state memory, optical media and magnetic media. Specific examples of machine-readable media include, by way of example, semiconductor memory devices (e.g., erasable programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM)) and flash memory devices, internal hard disks and Non-volatile memory including magnetic disks such as removable disks, magneto-optical disks, and CD-ROM and DVD-ROM disks. A “machine-readable storage medium” is also intended to include devices that may be interpreted as temporary, such as register memory, processor cache, and RAM, among others. The definitions provided herein for machine-readable media and machine-readable storage media are applicable even if the machine-readable medium is further characterized as “non-transitory”. For example, any addition of “non-transitory”, such as a non-transitory machine-readable storage medium, is intended to continue to include register memory, processor cache, and RAM, among other memory devices. A machine-readable storage medium or a computer-readable storage medium should be interpreted as a non-transitory physical device such as a hard drive or physical computer memory, but the same is true if it is indicated as a non-transitory computer-readable storage device. May be interpreted.

Transmission Medium The instructions 724 may also be transmitted or received via the communication network 726 using a transmission medium. The instructions 724 may be transmitted using the network interface device 720 and any one of several well-known transfer protocols (eg, HTTP). Examples of communication networks include LANs, WANs, the Internet, mobile phone networks, conventional telephone (POTS) networks, and wireless data networks (eg, WiFi networks and WiMax networks). The term “transmission medium” shall be construed to include any intangible medium capable of storing, encoding, or carrying instructions for execution by a machine and facilitates communication of such software. Includes digital or analog communication signals or other intangible media.

  Accordingly, a method and system for implant positioning device navigation and control has been described. Although the invention has been described with reference to particular exemplary embodiments, various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the invention. It will be clear that it is good. The specification and drawings are, accordingly, to be regarded in an illustrative sense rather than a restrictive sense.

  Although the embodiments have been described with reference to particular exemplary embodiments, various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the invention. It will be clear that it is good. The specification and drawings are, accordingly, to be regarded in an illustrative sense rather than a restrictive sense. The accompanying drawings, which form part of the invention, illustrate, by way of illustration and not limitation, specific embodiments in which the subject matter may be implemented. The illustrated embodiments are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed herein. Other embodiments may be used and derived from such that structural and logical substitutions and changes may be made without departing from the scope of the present disclosure. This detailed description is, therefore, not to be taken in a limiting sense, and the scope of the various embodiments is defined by the appended claims and the equivalents to which such claims are entitled. Is defined only by the full scope of

  Such embodiments of the present inventive subject matter are not intended to voluntarily limit the scope of the present application to any one invention or inventive concept, if more than one is actually disclosed. It may be referred to herein individually and / or collectively by simply the term “invention”. Thus, although particular embodiments or examples have been illustrated and described herein, any configuration calculated to achieve the same purpose may replace the particular embodiment shown. Should be understood. This disclosure is intended to cover any and all adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the above description.

  All publications, patents, and patent documents mentioned in this document are hereby incorporated by reference in their entirety as if individually incorporated by reference. In case of conflicting usage between this document and those documents so incorporated by reference, usage in the incorporated references should be considered as a supplement to the usage of this document. The usage in this document controls the inconsistencies that are present and incompatible.

  In this document, the term “a” or “an” is independent of any other example or “at least one” or “one or more” usage, as is common in patent documents. Used to include one or more. In this document, the term “or” means “A or B” includes “A not B”, “B not A”, and “A and B” unless otherwise indicated. , Non-exclusive, or used to refer to. In the appended claims, the terms “comprising” and “in” are used as plain English synonyms for the respective terms “comprising” and “in”. Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, elements in addition to those listed after such terms in the claims. A system, device, article or process comprising is still considered to be within the scope of the claims. Further, in the following claims, terms such as “first”, “second”, “third” are used merely as labels and impose numerical requirements on their subjects. Not intended.

  This summary of the disclosure is provided so as not to interpret or limit the scope or meaning of the claims to provide a brief summary of the subject matter of the disclosure. In addition, in the foregoing detailed description, it can be seen that various features are grouped together in a single embodiment for the purpose of streamlining the present disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim.

100 system, surgical setup
110 incision
120 patient tracking frame, tracking array
130 Graphical user interface, display device, monitor
140 Optical tracking system, tracking system
150 surgical cutting tools, surgical tools, surgical instruments
155 optical tracking frame, tracking array
200 systems
210 Control system
212 Planning Module
214 Navigation module
216 Control module
218 Communication interface
230 Database
600 physical world map
610 computer model diagram
620 starting model
625 surgical instrument model
630 Waste voxels
635 Waste voxels
640 Reshaping model
650 bone voxels
700 computer system
702 processor
704 Main memory
706 Static memory
708 bus
710 video display unit
712 alphanumeric input device
714 User Interface (UI) Navigation Device
716 disk drive unit
718 signal generation device
720 network interface device
722 machine-readable media
724 one or more sets of instructions and data structures, instructions
726 Communication network

Claims (20)

Using one or more processors to generate a three-dimensional (3D) model approximating the target bone;
Receiving a plurality of surface points from a portion of the target bone associated with an implant correction procedure from a tracking system that tracks a surgical instrument;
Generating a reshaped 3D model based on the 3D model and the plurality of surface points collected from the portion of the target bone using the one or more processors. Method.   The method of claim 1, further comprising generating a correction plan for preparing the target bone for implanting a prosthetic implant.   3. The method of claim 2, further comprising controlling a surgical cutting instrument that is tracked during the target bone resection according to the modification plan.   The method of claim 1, wherein the step of generating the 3D model comprises generating a voxelized 3D cylinder surrounding the portion of the target bone associated with the implant modification procedure.   The step of generating the 3D model includes generating a voxelized 3D model, and the step of generating the reshaped 3D model is the voxelized based on the plurality of surface points. The method of claim 1, comprising updating voxels in the 3D model.   6. The method of claim 5, wherein the step of updating voxels in the voxelized 3D model comprises performing volume subtraction from the 3D model based on the plurality of surface points.   Receiving a predefined set of parameters from a tracked surgical instrument that characterizes the target bone, and generating the 3D model includes generating the 3D model from the predefined set of parameters. The method of claim 1, comprising calculating bone dimensions of the bone.   The method of claim 1, wherein generating a reshaped 3D model occurs iteratively during collection of the plurality of surface points. A surgical instrument including a tracking array;
A tracking system including a tracking sensor, wherein the tracking system monitors in real time the 3D position and orientation of the surgical instrument and the 3D position and orientation of at least one target bone of the implant host; A tracking system;
A control system,
A communication interface coupled to the tracking system to receive tracking information identifying a current surgical instrument position and a current target bone position;
One or more processors coupled to a memory device, wherein the memory device is executed by the one or more processors;
Collecting pre-defined parameters characterizing the target bone from the tracking system based on the position of the surgical instrument relative to the target bone;
Generating a three-dimensional (3D) model of the target bone based at least in part on a portion of the predefined parameters;
Collecting, from the tracking system, a plurality of surface points from a portion of the target bone associated with an implant correction procedure based on the position of the surgical instrument relative to the target bone;
Instructions for causing the control system to perform an action comprising generating a reshaped 3D model based on the 3D model and the plurality of surface points collected from the portion of the target bone. And a control system comprising one or more processors.   The system of claim 9, wherein the surgical instrument includes at least one of a cutting bar, a bar guard, a flat probe attachment, and a point probe.   The collecting of the predefined parameter or the plurality of surface points is performed using one of the cutting bar, the bar guard, the flat probe attachment, and the point probe. The system described in.   The system of claim 9, wherein the control system further performs an operation that includes generating a correction plan for preparing the target bone for implanting a prosthetic implant. The communication interface is coupled to the surgical instrument to send a control signal to control the cutting bar;
The control system is
Generating control signals to control the surgical instrument during resection of the target bone according to the modification plan;
The system of claim 12, further comprising performing an operation comprising communicating the generated control signal to the surgical instrument via the communication interface.   The system of claim 9, wherein the generating the 3D model includes generating a voxelized 3D cylinder surrounding the portion of the target bone associated with the implant modification procedure.   15. The system of claim 14, wherein generating the reshaped 3D model includes performing volume subtraction from the 3D model based on the plurality of surface points.   The system of claim 9, wherein the generating the 3D model includes accessing a pre-operative medical image of the target bone to generate the 3D model.   The system of claim 9, wherein generating a reshaped 3D model occurs iteratively during collection of the plurality of surface points. When executed by machine
Generating a three-dimensional (3D) model of the target bone based at least in part on parameters characterizing the target bone using one or more processors in the machine;
Receiving a plurality of surface points from a portion of the target bone associated with an implant correction procedure from a tracking system that tracks the surgical instrument being tracked;
Generating a reshaped 3D model based on the 3D model and the plurality of surface points collected from the portion of the target bone using the one or more processors; A machine-readable storage device comprising instructions that cause the machine to perform operations including. The instructions further comprise instructions for causing the machine to generate a correction plan to prepare the target bone for implanting a prosthetic implant;
The machine-readable storage device of claim 18, wherein the instructions further comprise instructions that cause the machine to control a surgical cutting instrument that is tracked during resection of the target bone according to the modification plan. Using one or more processors to generate a three-dimensional (3D) voxelized model of the target bone portion associated with the implant modification procedure, the model at least in all dimensions; A step that is as large as said portion of the target bone;
Receiving a plurality of data points as the instrument is traced along the surface of the target bone from a tracking system that tracks an instrument of known geometry;
Using one or more processors to calculate a set of discarded voxels to be removed from the model based at least in part on the plurality of data points;
Generating a reshaped 3D voxelization model based on the set of discarded voxels using the one or more processors.